S. B. Dugdale1, H. M. Fretwell1, M. A. Alam1, R. N. West2, N. Shiotani3, G. Kontrym-Sznajd4
1 H. H. Wills Physics Laboratory, University of Bristol, Tyndall Ave., Bristol BS8 1TL, UK,
2 Department of Physics, University of Texas, Arlington, Texas, USA,
3 Physics Laboratory, Tokyo University of Fisheries, Kounan, Minato, Tokyo 108, Japan,
4 Polish Academy of Sciences, W. Trzebiatowski Institute of Low Temperature and Structure Research, 50-950 Wroclaw 2, P.O. Box 937, Poland
Two dimensional angular correlation of positron annihilation radiation (2D-ACAR) and the measurement of Compton profiles provide complementary methods of investigating electronic structure. In 2D-ACAR experiment, one obtains a 2D projection of the underlying electron-positron momentum density, while a Compton profile yields a doubly integrated (1D) projection of the electron momentum density. One of the major research themes of the Bristol group has been concerned with the retrieval of Fermi surface (FS) information from measured 2D-ACAR spectra, employing Maximum Entropy deconvolution and reconstruction techniques. When these are used together, the result is significantly enhanced reconstructions, containing shaper FS-related structures. Although free from positron-induced perturbations, it is only recently that high-resolution (~0.1 a.u. FWHM) Compton data have become available. A preliminary study has shown that the application of the Maximum Entropy technique to the Compton profiles, enables direct FS information to be extracted from the data.